result of a detailed study of the question she concluded that the inscriptional ribs represented not dermal elements, but cartilage bones similar to the ventral portions of true ribs in lizards. They thus cannot be included with the “ossa investitientia” (Gaupp) as can the sternal bones of primitive vertebrates (e.g. the abdominal ribs of Sphenodon, Crocodilia, Archaeopteryx, many fossil reptiles and certain Stegocephalia), “which do not pass through a cartilaginous stage, but ossify directly in the connective tissue of the cutis”. Certainly, the inscriptional ribs of Leiopelma do have their earliest origins as strips of cartilage, and remain cartilaginous until fairly late maturity. They form a continuous series with the cartilaginous styles of the sternum. Some variations in the cartilages are shown in Text-fig. 4; e.g. they may not reach each other, or they may overlap or fuse in the middle line. One mature L. hochstetteri prepared by means of the alizarin and toluidin blue method of Williams (1940) showed distinct alizarin staining in the cartilages (Text-figure 4 A). Obviously, then, the inscriptional ribs must become calcified or ossified in later life.